The current study investigates the characteristics of particles generated from the wear of braking materials, and provides an applicable index for measuring and comparing wear particle emissions. A pin-on-disc tribometer equipped with particle measurement instruments was used. The number concentration, size, morphology, and mass concentration of generated particles were investigated and reported for particles 10 nm-32 mu m in diameter. The particles were also collected on filters and investigated using EDS and SEM. The effects of wear mechanisms on particle morphology and changes in particle concentration are discussed. A new index, the airborne wear particle emission rate (AWPER), is suggested that could be used in legislation to control non-exhaust emissions from transport modes, particularly rail transport.

Inhalable airborne particles have inverse health affect. In railways, mechanical brakes, the wheel–rail contact, current collectors, ballast, sleepers, and masonry structures yield particulate matter. Field tests examined a Swedish track using a train instrumented with particle measurement devices, brake pad temperature sensors, and speed and brake sensors. The main objective of this field test was to study the characteristics of particles generated from disc brakes on a running train with an on-board measuring set-up.

Two airborne particle sampling points were designated, one near a pad–rotor disc brake contact and a second under the frame, not near a mechanical brake or the wheel–rail contact; the numbers and size distributions of the particles detected were registered and evaluated under various conditions (e.g. activating/deactivating electrical brakes or negotiating curves). During braking, three speed/temperature-dependent particle peaks were identified in the fine region, representing particles 280 nm, 350 nm, and 600 nm in diameter. In the coarse region, a peak was discerned for particles 3–6 μm in diameter. Effects of brake pad temperature on particle size distribution were also investigated. Results indicate that the 280 nm peak increased with increasing temperature, and that electrical braking significantly reduced airborne particle numbers. FESEM images captured particles sizing down to 50 nm. The ICP-MS results indicated that Fe, Cu, Zn, Al, Ca, and Mg were the main elements constituting the particles.

Brake pads on wheel-mounted disc brakes are often used in rail transport due to their good thermal properties and robustness. During braking, both the disc and the pads are worn. This wear process generates particles that may become airborne and thus affect human health. The long term purpose of ‘Airborne particles in Rail transport’ project is to gain knowledge on the wear mechanisms in order to find means of controlling the number and size distribution of airborne particles. In this regard, a series of full-scale field tests and laboratory tests with a pin-on-disc machine have been conducted. The morphology and the matter of particles, along with their size distribution and concentration, have been studied. The validity of results from the pin-on-disc simulation has been verified by the field test results. Results show an ultra-fine peak for particles with a diameter size around 100 nm in diameter, a dominant fine peak for particles with a size of around 350 nm in diameter, and a coarse peak with a size of 3-7 μm in diameter. Materials such as iron, copper, aluminium, chromium, cobalt, antimony, and zinc have been detected in the nano-sized particles.

The economic viability of novel energy-efficient design concepts has been evaluated in Finnish educational buildings. The total energy consumption of representative target buildings with each design concept has been found using the whole-building simulation tool IDA Indoor Climate and Energy 4.0, and the financial viability has been assessed using the discounted payback period method. Different thermal insulation and air tightness properties of the building envelope, and different ventilation's heat recovery efficiency assumptions and heat distribution options have been investigated. The results suggest that a prudent attitude should be taken toward the investments in ultra-low-energy designs. Total energy-saving potential of 25-32% can be obtained. The payback periods varied from 15 to more than 40 years. The results can be generalized in cold climates and techno-economic conditions similar to Finland.

This paper presents results from European Union projects on ductwork quality tightness. The projects were done in Sweden, Belgium, and France. The tightness on a large number of ductwork installations in the three countries was compared and it was found that there is a tremendous difference in tightness. The answer to the question, "Why this large difference between the countries?" is most probably that Sweden has been requiring tight ducts, i.e., specifying how much they are allowed to leak at a certain test pressure, whereas in the two other countries, tightness of ductwork is normally neither required nor tested.

6.

Ansell, Anders

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.

Holmgren, Jonas

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.

Mundt, Elisabeth

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.

Silfwerbrandt, Johan

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.

Stille, Håkan

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.

Sundquist, Håkan

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.

The Supervisory Control And Data Acquisition (SCADA) system is used as a front-end for the Building Energy Management System (BEMS). There are many factors that can affect the choice of the SCADA system. In this study,we tried to measure how different categories of people (i.e. buyers and users of these systems) evaluated 21 different factors that could influence the system choice. The study was conducted through a Web-based poll that was e-mailed out to buyers and users in the public and private sectors in Sweden. The result was evaluated by using statistical methods and significant differences were found in how buyers and users evaluated different factors. In addition, significant differences in answers were found based on the respondents'main fields of competency.

According to a decision of the European Commission, measures are to be taken to reduce the use of energy in the EU. The goal is to reduce it by 20 % compared to the current use. This shall be done to the year 2020 (European Commission, 2011). One industry that use large amounts of energy is the construction of buildings which account for almost a third of the energy use (Brogren, 2012). The major part of the energy that is used in the construction industry is not used when the buildings are built, but rather during the rest of their subsequent lifetime. There is a great potential to save energy by reducing the energy that is used to maintain a satisfactory indoor climate. Recovery of excess heat and excess cold is a solution that the European Commission think has the biggest potential to reduce the total energy consumption.

The most common system used for energy recovery is air to air heat exchangers connected with the supply air and the exhaust air. For different reasons it is not possible to use this kind of system in several buildings. If that is the case there is a possibility to use a liquid coupled recovery system instead. If an additional source of excess heat or excess cooling exist within the building, or nearby, it is also possible to connect this to the system which would increase the ability to save energy even more.

The purpose of this thesis has been to develop a tool for energy calculations in liquid-coupled recovery systems. This tool has been developed in the program IDA ICE (used for energy calculations) and has made it possible to perform dynamic simulations in this kind of system over the timeframe of a whole year and with a very short calculation time. The tool is flexible in terms of its components and system design so it can be used for several different types of projects. Everything from simple systems with fixed brine flow with only one supply air and exhaust air unit to systems with several units, various types of control possibilities and an addition of excess heat from, for example, a room containing computer servers.

The tool that has been developed has been verified and used to calculate the potential to save energy in a system that is installed at the Ångström laboratory in Uppsala. The tool has shown that with the kind of control and the conditions that currently exist at the laboratory the energy consumption could be reduced by 444 MWh which in this case almost is 50 % of the current energy consumption. Besides the recovery system in Ångström two more systems have been investigated, a server room for The Royal Institute of Technology and the server halls that Facebook is building near Luleå town. The investigation shows that there exist very large amounts of heat that is possible to recover in buildings that include server rooms and that the installed recovery systems, if there are any, in many cases could be improved.

Besides constructing recovery systems that recover heat or cold in buildings it is also possible to build this kind of system that recover heat or cold between buildings in the same area. The tool can also be used to investigate how such a system should work in order to minimize the use of energy as much as possible. A solution where heat and cold is recovered between multiple buildings is a solution that probably will be very interesting in the future, which means that this tool could come in handy.

Much attention is given to the consequences of airborne particles on human health and well-being. Wear is one source of airborne particles and contributions in the urban environments from wheel-to-rail contacts and disc brakes cannot be neglected. Traditionally, mechanical wear has been associated with the generation of particles of diameters of some microns. However, the research described has found ultrafine particle generation from wear processes. Particle generation from wear was measured under controlled laboratory conditions. The wear was created through sliding contact in a tribometer (type "pin-on-disc") with different materials and with different sliding velocities and pressures, to represent rail traffic and automobile disc braking. Particle concentrations and size distributions in the air were determined for particle diameters from 10 nm up to more than 10 mu m. For most materials and conditions three particle size modes were found: one at 50-100 nm, one at a few hundred nm and one at a few mu m particle diameter.

33.

Jansson, Gustav

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.

Lundberg, Tobias

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.

Based on the comparative analysis of the experimental values determined for the tribological parameters for the three novel nano-porous composition base and two conventional brake lining materials while friction with the grey cast iron disc, it was shown the considerable high tribological efficiency of the novel nano-porous composition base lining materials in comparison with the conventional (from EU and USA market) brake lining materials. The explanation is given to the action mechanism of nano-porous composition base brake lining material and its tribological efficiency basing on the "triple phase" tribo-pair model.

The starting point for this master thesis was the product of the company "Humlegården", which allows its tenants in office buildings to follow their electricity consumption in real time, through their Smartphone's. The idea that resulted from that application is to investigate if it is possible to direct the tenants in office buildings to reduce their energy consumptions, but also to be satisfied with the indoor environment. This work addresses the factors which are the main energy consumers in office buildings. It addresses legal requirements and standards which are important to follow in order to achieve good thermal comfort in buildings. Some of them are physical climate factors like thermal environment, air quality and lightning. Investigation has also been made on psychological, physiological and social factors which are important for human’s thermal perception. Even monitoring methods for energy and comfort have been discussed as well as methods that are used to ensure the thermal perception of human beings. Through literature studies that have been carried out in the past, especially those who determine the connection between physical and psycho-social elements, a simple suggestion has been made. The suggestion is based on indoor and outdoor temperature, that should direct the tenant to allow in some cases lower indoor temperature which will lead to minimized energy consumption.

With the result from the book "Cleanroom Clothing Systems, People as a contamination source" (1), some calculations are given, describing predicted contamination levels in cleanrooms with turbulent mixing air and cleanrooms with vertical unidirectional air flow when people are dressed in modern cleanroom clothing systems which have been used and washed several times.

40.

Ljungqvist, Bengt

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

Reinmüller, Berit

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

A comparison of data acquired from simultaneous measurements by IMD-A, standard OPC and STA-sampler during evaluations in a test chamber will be presented. Pros and cons of different instruments will be discussed.

41.

Ljungqvist, Bengt

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.

Reinmüller, Berit

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.

In cleanrooms the main source of biocontamination is people. The concentration of airborne biocontamination depends upon the number of people present in a cleanroom, their level of activity, and the clothing systems used. There are several methods of measuring the airborne biocontamination and many published reports show that the results - as number of colony forming units per cubic meter (CFU/m3) - depend on the equipment used. The difference in results between microbiological air samplers often depend upon physical parameters of the samplers. These parameters, together with d50 that is the aerodynamic particle diameter where 50% of the particles are collected and 50% are not collected are discussed. In order to evaluate the collection efficiency of impaction air samplers, a simplified mathematical model will be presented and examples given.

43.

Ljungqvist, Bengt

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

Reinmüller, Berit

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

To interpret the results from viable air sampling, the user should understand the dynamics of sampling and collection of particles on the collection medium. Results of 0 CFU per cubic meter in manned cleanrooms could indicate that the sampling process, sampling location or the collection media, incubation temperature and time have not been optimized. It is important to be aware of the limitations of each sampling method. Results from one sampling method must not be compared with results obtained by another method without careful investigation. To improve the evaluation of controlled environments based on achieved results, the air sampler used has to be specified. An air sampler should be selected based upon a thorough evaluation of the characteristics of the sampler, the sampling conditions and sampling requirements.

44.

Ljungqvist, Bengt

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.

Reinmüller, Berit

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.

Using a modified dispersal chamber, the authors have studied the protective efficacy of cleanroom clothing systems. Study results show that the state of a cleanroom clothing system-new or much used-influences the protection efficacy of the system. Suitable combinations of cleanroom underwear and cleanroom garments also improve the protection of the clean environment against airborne contaminants from people.

47.

Ljungqvist, Bengt

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

Reinmüller, Berit

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

In cleanrooms the main source of biocontamination is people. The concentration of airborne biocontamination depends upon the number of people present in a cleanroom, their level of activity, and the clothing systems used. There are several methods of measuring the airborne biocontamination and many published reports show that the results - as number of colony forming units per cubic meter (CFU/m3) - depend on the equipment used. The difference in results between microbiological air samplers often depend upon physical parameters of the samplers. These parameters, together with d50 that is the aerodynamic particle diameter where 50% of the particles are collected and 50% are not collected are discussed. In order to evaluate the collection efficiency of impaction air samplers, a simplified mathematical model will be presented and examples given.

48.

Ljungqvist, Bengt

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

Reinmüller, Berit

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

Clothing systems used in operating rooms are compared to clothing systems used in food industry and in pharmaceutical manufacturing. For all these industries the control of the concentration of airborne bacteria-carrying particles are of vital importance. The emission of large particles with regard to clothing system quality is commented. Results from the study can be used to calculate expected concentrations of airborne aerobic colony forming units in the operation room when clothing system and number of people in the room are known. The study shows that the commonly used protective clothing systems need to be upgraded in operation rooms where patients, sensitive to infections undergo operations.

50.

Ljungqvist, Bengt

et al.

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).

Reinmüller, Berit

KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering (name changed to Building Service and Energy Systems 2012-03-01).